Synthesis of 1,4-benzodioxan derivatives and the evaluation of their biological activity as a novel juvenile hormone signaling inhibitor.

BACKGROUND: Juvenile hormone (JH) signaling inhibitors may be used as insect growth regulators because of their ability to control metamorphosis and reproduction in insects by regulating the action of JH. RESULTS: We identified ethyl (E)-3-(4-{[7- (4-methoxycarbonylbenzyloxy)-1,4-benzodioxan-6-yl]methyl}phenyl)prop-2-enoate (EMBP) and observed its strong precocious metamorphosis-inducing activity against silkworm larvae. To further elucidate its mechanism of action, we investigated the effect of EMBP on the JH-mediated signaling pathway in vitro and in vivo. In a reporter assay using a Bombyx mori cell line, EMBP strongly suppressed the induction of reporter gene expression by Juvenile hormone I (JH I) in a concentration-dependent manner. A parallel rightward shift was observed in the dose-response curve of JH I after treatment with EMBP, indicating that EMBP competitively inhibited JH. Moreover, we monitored developmental changes in the JH-responsive gene, Krüppel homolog 1 (Kr-h1), and ecdysone-responsive gene, Broad-Complex (BRC), in EMBP-treated silkworm larvae. EMBP suppressed only the expression of Kr-h1 in third-instar larvae. CONCLUSION: Our results demonstrated that EMBP specifically regulates the JH-mediated Kr-h1 signaling pathway. EMBP could be used as a lead compound in the development of new insect growth regulators. © 2023 Society of Chemical Industry.

Identification of novel juvenile-hormone signaling activators via high-throughput screening with a chemical library.

Juvenile hormone (JH) is an insect-specific hormone that regulates molting and metamorphosis. Hence, JH signaling inhibitors (JHSIs) and activators (JHSAs) can be used as effective insect growth regulators (IGRs) for pest management. In our previous study, we established a high-throughput screening (HTS) system for exploration of novel JHSIs and JHSAs using a Bombyx mori cell line (BmN_JF&AR cells) and succeeded in identifying novel JHSIs from a chemical library. Here, we searched for novel JHSAs using this system. The four-step HTS yielded 10 compounds as candidate JHSAs; some of these compounds showed novel basic structures, whereas the others were composed of a 4-phenoxyphenoxymethyl skeleton, the basic structure of several existing JH analogs (pyriproxyfen and fenoxycarb). Topical application of seven compounds to B. mori larvae significantly prolonged the larval period, suggesting that the identified JHSAs may be promising IGRs targeting the JH signaling pathway.

Identification of a juvenile-hormone signaling inhibitor via high-throughput screening of a chemical library.

Insecticide resistance has recently become a serious problem in the agricultural field. Development of insecticides with new mechanisms of action is essential to overcome this limitation. Juvenile hormone (JH) is an insect-specific hormone that plays key roles in maintaining the larval stage of insects. Hence, JH signaling pathway is considered a suitable target in the development of novel insecticides; however, only a few JH signaling inhibitors (JHSIs) have been reported, and no practical JHSIs have been developed. Here, we established a high-throughput screening (HTS) system for exploration of novel JHSIs using a Bombyx mori cell line (BmN_JF&AR cells) and carried out a large-scale screening in this cell line using a chemical library. The four-step HTS yielded 69 compounds as candidate JHSIs. Topical application of JHSI48 to B. mori larvae caused precocious metamorphosis. In ex vivo culture of the epidermis, JHSI48 suppressed the expression of the Krüppel homolog 1 gene, which is directly activated by JH-liganded receptor. Moreover, JHSI48 caused a parallel rightward shift in the JH response curve, suggesting that JHSI48 possesses a competitive antagonist-like activity. Thus, large-scale HTS using chemical libraries may have applications in development of future insecticides targeting the JH signaling pathway.

Prognostic significance of crazy paving ground grass opacities in non-HIV Pneumocystis jirovecii pneumonia: an observational cohort study.

BACKGROUND: In patients with non-HIV Pneumocystis jirovecii pneumonia (PjP), computed tomography imaging reveals ground grass opacities (GGO). Previous reports show that some patients with non-HIV PjP exhibit GGO with crazy paving. However, there have been no studies on the association between crazy paving GGO and non-HIV PjP clinical outcomes. Here, at the diagnosis of non-HIV PjP, we reviewed high-resolution computed tomography (HRCT) findings that included GGO types and evaluated the prognostic impact of crazy paving GGO on the clinical outcomes of non-HIV PjP immunocompromised patients. METHODS: We retrospectively reviewed the clinical information including the HRCT findings of patients diagnosed with non-HIV PjP from five institutions between 2006 and 2015. The GGO types included those with or without crazy paving. The associations between clinical factors such as HRCT findings and in-hospital mortality were assessed using the Cox regression model. RESULTS: Sixty-one patients were included in our study. Nineteen patients died at a hospital. All patients exhibited GGO on HRCT imaging at diagnosis of non-HIV PjP. The HRCT findings included crazy paving GGO (29 patients, 47.5%), consolidations (23 patients, 37.7%), bronchiectasis (14 patients, 23.0%), and centrilobular small nodules (30 patients, 49.2%). Cysts were not observed in any patient. Multivariate analysis revealed that crazy paving GGO and low serum albumin levels were independent risk factors for mortality. CONCLUSIONS: At the diagnosis of non-HIV PjP, patients with crazy paving GGO on HRCT imaging and low serum albumin levels may have a poor prognosis.

4-Aryl-5-carbamoyl-3-isoxazolols as competitive antagonists of insect GABA receptors: Synthesis, biological activity, and molecular docking studies.

Competitive antagonists (CAs) of ionotropic GABA receptors (GABARs) reportedly exhibit insecticidal activity and have potential for development as novel insecticides for overcoming emerging resistance to traditional GABAR-targeting insecticides. Our previous studies demonstrated that 4,5-disubstituted 3-isoxazolols or 3-isothiazolols are an important class of insect GABAR CAs. In the present study, we synthesized a series of 4-aryl-5-carbamoyl-3-isoxazolols and examined their antagonism of insect GABARs expressed in Xenopus oocytes. Several of these 3-isoxazolols exhibited potent antagonistic activities against housefly and common cutworm GABARs, with IC50 values in the low-micromolar range in both receptors. 4-(3-Amino-4-methylphenyl)-5-carbamoyl-3-isoxazolol (3u) displayed the highest antagonism, with IC50 values of 2.0 and 0.9 µM in housefly and common cutworm GABARs, respectively. Most of the synthesized 3-isoxazolols showed moderate larvicidal activities against common cutworms, with more than 50% mortality at 100 µg/g. These results indicate that 4-monocyclic aryl-5-carbamoyl-3-isoxazolol is a promising scaffold for insect GABAR CA discovery and provide important information for the design and development of GABAR-targeting insecticides with a novel mode of action.

18 Cases of pulmonary Mycobacterium abscessus: Clinical difference depending on the presence or absence of Mycobacterium avium complex.

BACKGROUND AND OBJECTIVES: It can be difficult to treat respiratory tract infections caused by Mycobacterium abscessus (M. abscessus) as there is no established treatment strategy. Complications involving other nontuberculous mycobacterial infections such as Mycobacterium avium complex (MAC) are also commonly observed. METHODS: We investigated the clinical background and course of 18 cases of pulmonary M. abscessus infection treated over 8 years at Kurashiki Central Hospital. Radiological evaluation was performed using NICE scoring system, a method of semi-quantitative evaluation of imaging findings of pulmonary MAC infection. RESULTS: The mean age of the 18 patients (males, 6; females, 12) was 74.7 years. The median follow-up period was 1316 days (95% confidence interval; 720-1675 days), and 11 patients were concomitantly infected with pulmonary MAC. Among the patients that underwent antibacterial treatment for M. abscessus, there was one MAC-complication case and one non-MAC-complication case. All MAC-complication cases underwent antibacterial treatment including clarithromycin. Chest X-ray NICE scores for all cases were 8.50 ± 5.45 and 10.94 ± 6.03 at baseline and follow-up, respectively (p = 0.0063). For MAC-complication cases, scores were 8.36 ± 4.74 and 12.00 ± 6.02 at baseline and follow-up, respectively (p = 0.00818), and for non-MAC-complication cases, scores were 8.71 ± 6.82 and 9.29 ± 6.13 at baseline and follow-up, respectively (p = 0.356). MAC-complication cases were significantly further exacerbated than non-MAC-complication cases (p = 0.027). CONCLUSIONS: Some cases of pulmonary M. abscessus infection progressed well without undergoing antibacterial treatment. In particular, results suggested that the clinical course of MAC-complication and non-MAC-complication cases differs.

Pneumocystis pneumonia associated with human immunodeficiency virus infection without elevated (1 → 3)-ß-D glucan: A case report.

Pneumocystis pneumonia (PCP) caused by Pneumocystis jirovecii is one of the most common opportunistic infections in immunosuppressed patients, particularly in patients with acquired immunodeficiency syndrome (AIDS). (1 â†’ 3)-ß-D-glucan is a component of the cell wall of P. jirovecii and other fungi such as Candida sp., Aspergillus sp. and Histoplasma sp. The measurement of serum (1 â†’ 3)-ß-D-glucan has been reported to be a highly sensitive test for PCP related to human immunodeficiency virus (HIV-PCP). We report a case of HIV-PCP not associated with elevated serum (1 â†’ 3)-ß-D glucan and highlight how HIV-PCP cannot be completely ruled out if (1 â†’ 3)-ß-D glucan is negative.

Drug-induced lung injury associated with combination therapy of daclatasvir and asunaprevir: The first case report.

Combination therapy with direct acting antiviral agents (DAAs) without interferon (IFN) has emerged as a treatment for chronic hepatitis C because of its high overall sustained virologic response rates and favorable side effect profile as compared to that with interferon. We report the first case of drug-induced lung injury (DLI) associated with IFN-free therapy with the DAAs, daclatasvir (NS5A inhibitor) and asunaprevir (NS3/4A protease inhibitor). Although this combination therapy of DAAs has been considered to have fewer side effects than IFN, more attention should be paid to DLI as an important side effect.

Anti-juvenile hormone activity of ethyl 4-[(7-substituted 1,4-benzodioxan-6-yl)methyl]benzoates and their effect on the juvenile hormone titer in the hemolymph of the silkworm, Bombyx mori.

A series of ethyl 4-[(7-substituted 1,4-benzodioxan-6-yl)methyl]benzoates was synthesized and evaluated for their anti-juvenile hormone (anti-JH) activities to induce precocious metamorphosis in silkworm (Bombyx mori) larvae. The introduction of bulky alkyloxy substituents on the 7-position on the benzodioxan ring significantly increased activity. Ethyl 4-[(7-benzyloxy-1,4-benzodioxan-6-yl)methyl]benzoate (4c) showed the most potent activity among the test compounds, and its median-effective dose (ED50) value was 41 ng/larva. The JH I, II, and III concentrations in the hemolymph of the 3rd instar larvae treated with compound 4c were determined by ultra-high-performance liquid chromatography/mass spectrometry (UHPLC/MS) after using a simple purification method. Compound 4c clearly decreased the JH I and II titers of 3rd instar larvae within 24 hr after treatment, and prevented JH I spike usually found immediately after 4th instar molting.

[A Study on the Clinical Course and Antimicrobial Susceptibility of Mycoplasma pneumoniae in a Community Hospital].

Recently, reports of macrolide-resistant strains of Mycoplasma pneumoniae have been increasing. We examined the antimicrobial susceptibility and clinical significance in patients with M. pneumoniae. Seventy patients in whom M. pneumoniae was detected from 2008 to 2012 were included in the study, and compared with patients between 2003 and 2006. There were no macrolide-resistant strains detected in the 38 strains from 2003 to 2006, but from 2008 to 2012, out of the 70 strains 46 (65.7%) were positive for the macrolide-resistant 23SrRNA gene mutant (A2063G), which is consistent with recent trends. Comparison between cases of macrolide resistant strains and those with macrolide sensitive strains did not reveal a significant difference in the hospitalization period. The approximate duration of fever was 7 days; for both cases: those who received effective antimicrobials as the initial therapy, and for those with macrolide sensitive strains. It seems that the duration of fever depends on susceptibility to the initial antimicrobials regardless of macrolide resistance. There were some patients that improved without use of quinolone or minocycline, though macrolide-resistant strains were detected. These patients did not reveal extension of the hospital stay nor aggravation of pneumonia. This suggests that a macrolide drug might be the first choice drug for M. pneumoniae even now, and a change of drug should be considered when fever duration is long.

Identifying the Cause of the "Saturation Gap": Two Cases of Dapsone-induced Methemoglobinemia.

Diaphenylsulfone (DDS: Dapsone) is used for Pneumocystis pneumonia (PCP) prophylaxis, and methemoglobinemia has rarely been reported as a side effect of DDS. We herein report two cases of DDS-related methemoglobinemia in an 81-year-old man with organizing pneumonia and an 84-year-old woman with eosinophilic pneumonia under treatment with prednisolone. Both patients initially received trimethoprim/sulfamethoxazole for PCP prophylaxis and were switched to DDS due to side effects and subsequently exhibited a clinically unexplainable decrease in SpO2. Methemoglobinemia was diagnosed based on the findings of arterial blood gas analyses. In both cases, the methemoglobinemia improved after discontinuing DDS.

4,5-Substituted 3-Isoxazolols with Insecticidal Activity Act as Competitive Antagonists of Housefly GABA Receptors.

The insect GABA receptor (GABAR), which is composed of five RDL subunits, represents an important target for insecticides. A series of 4,5-disubstituted 3-isoxazolols, including muscimol analogues, were synthesized and examined for their activities against four splice variants (ac, ad, bc, and bd) of housefly GABARs expressed in Xenopus oocytes. Muscimol was a more potent agonist than GABA in all four splice variants, whereas synthesized analogues did not exhibit agonism but rather antagonism in housefly GABARs. The introduction of bicyclic aromatic groups at the 4-position of muscimol and the simultaneous replacement of the aminomethyl group with a carbamoyl group at the 5-position to afford six 4-aryl-5-carbamoyl-3-isoxazolols resulted in compounds that exhibited significantly enhanced antagonism with IC50 values in the low micromolar range in the ac variant. The inhibition of GABA-induced currents by 100 µM analogues was approximately 1.5-4-fold greater in the ac and bc variants than in the ad and bd variants. 4-(3-Biphenylyl)-5-carbamoyl-3-isoxazolol displayed competitive antagonism, with IC50 values of 30, 34, 107, and 96 µM in the ac, bc, ad, and bd variants, respectively, and exhibited moderate insecticidal activity against houseflies, with an LD50 value of 5.6 nmol/fly. These findings suggest that these 3-isoxazolol analogues are novel lead compounds for the design and development of insecticides that target the orthosteric site of housefly GABARs.

Incidence and impact of interstitial lung disease and malignancy in patients with polymyositis, dermatomyositis, and clinically amyopathic dermatomyositis: a retrospective cohort study.

The aims of this study were to retrospectively review Japanese consecutive cases of polymyositis (PM), dermatomyositis (DM), and clinically amyopathic dermatomyositis (CADM), focusing on interstital lung disease (ILD) and malignancy, and to document any differences in the incidence, clinical features, and impact on prognosis among patients with PM, DM, and CADM. We retrospectively reviewed 62 consecutive patients diagnosed with PM, DM, and CADM according to Bohan and Peter's criteria (PM/DM) and Sontheimer's criteria and Gerami's criteria (CADM), focusing on ILD and malignancy. ILD occurrence rates were 48 % (11/23) in patients with PM, 46 % (11/24) in DM, and 100 % (15/15) in CADM. Malignancy occurred during diagnosis or the observation period in 14 patients; 86 % were without ILD, and 64 % were DM without ILD. Multivariate logistic regression analysis showed that the risk of newly diagnosed malignancy was significantly lower in patients with ILD [odds ratio, 0.0688; 95 % confidence interval (CI), 0.00127-0.372; p = 0.00190] and significantly higher in patients with DM (odds ratio, 5.21; 95 % CI, 1.17-23.1; p = 0.0299) than in other patients. Patients with malignancies had shorter survival than those without malignancies; no clinically meaningful difference in survival was observed among the different myositis types and for presence of ILD. In CADM-ILD, 80 % fatal cases died from refractory ILD ≤90 days from the first visit; neither death nor recurrence occurred subsequently. In conclusion, a positive association between DM and malignancy and a negative association between ILD and malignancy were noted. In the present study, malignancy was a predictor of poor long-term prognosis, but ILD were not. ILD associated with CADM contributed greatly to poor short-term prognosis, but neither death nor recurrence occurred subsequently.

Clinical characteristics of pneumonia in bedridden patients receiving home care: a 3-year prospective observational study.

BACKGROUND: The aim of the study was to describe the epidemiology, clinical features, antimicrobial treatment, and outcomes of bedridden pneumonia patients receiving home healthcare. METHODS: A 3-year prospective observational study of poor performance status (PS) 3-4 patients receiving long-term home healthcare and hospitalized at a single center with pneumonia between October 2010 and September 2013 was conducted, and their clinical characteristics were compared with non-bedridden community-acquired pneumonia (CAP) patients. RESULTS: A total of 131 CAP patients with PS 3-4, and 400 CAP patients with PS 0-2 were evaluated. The PS 3-4 patients were older, and exhibited a higher frequency of underlying diseases. Aspiration was thought to be associated with pneumonia in 77.1% of the PS 3-4 patients. Streptococcus pneumoniae was the leading pathogen in both groups, whereas the frequency of streptococci and polymicrobial infections was higher in the PS 3-4 group. The incidence of multidrug-resistant pathogens such as methicillin-resistant Staphylococcus aureus (MRSA) or Pseudomonas aeruginosa was lower than in previous healthcare-associated pneumonia reports. The in-hospital mortality and recurrence rates were significantly higher in the PS 3-4 group than in the good PS group (17.6% vs. 6.0%, p < 0.001 and 15.3% vs. 7.5%, p = 0.008, respectively). CONCLUSIONS: The clinical characteristics of pneumonia in poor PS patients were similar to healthcare-associated pneumonia (HCAP), except for the frequency of drug-resistant pathogens. Hence, it might be beneficial to categorize pneumonia in home residents with poor PS separately from pneumonia in CAP patients who were previously healthy or experienced mild comorbidities.

Chronological assessment of airway lesions in relapsing polychondritis by positron emission tomography.

A 40-year old woman presented with pyrexia, productive cough, and bilateral precordial pain. Positron emission tomography (PET)-computed tomography (CT) showed high, diffuse F-18 deoxyglucose accumulation in the tracheal, peribronchial, and bilateral costal cartilage. We diagnosed her with relapsing polychondritis (RP) based on McAdam's criteria. Airway lesions are a major prognostic indicator of RP, and so chronological assessment and control is essential. In this patient, PET-CT accurately reflected both the location and severity of the inflammation and helped to guide treatment decision-making and facilitated early detection of recurrence. However, its high cost is prohibitive to frequent use, making it necessary to comprehensively evaluate serum C-reactive protein levels, bronchoscopy, spirometry, and 3D-CT.

Methyl farnesoate synthesis is necessary for the environmental sex determination in the water flea Daphnia pulex.

Sex-determination systems can be divided into two groups: genotypic sex determination (GSD) and environmental sex determination (ESD). ESD is an adaptive life-history strategy that allows control of sex in response to environmental cues in order to optimize fitness. However, the molecular basis of ESD remains largely unknown. The micro crustacean Daphnia pulex exhibits ESD in response to various external stimuli. Although methyl farnesoate (MF: putative juvenile hormone, JH, in daphnids) has been reported to induce male production in daphnids, the role of MF as a sex-determining factor remains elusive due to the lack of a suitable model system for its study. Here, we establish such a system for ESD studies in D. pulex. The WTN6 strain switches from producing females to producing males in response to the shortened day condition, while the MFP strain only produces females, irrespective of day-length. To clarify whether MF has a novel physiological role as a sex-determining factor in D. pulex, we demonstrate that a MF/JH biosynthesis inhibitor suppressed male production in WTN6 strain reared under the male-inducible condition, shortened day-length. Moreover, we show that juvenile hormone acid O-methyltransferase (JHAMT), a critical enzyme of MF/JH biosynthesis, displays MF-generating activity by catalyzing farnesoic acid. Expression of the JHAMT gene increased significantly just before the MF-sensitive period for male production in the WTN6 strain, but not in the MFP strain, when maintained under male-inducible conditions. These results suggest that MF synthesis regulated by JHAMT is necessary for male offspring production in D. pulex. Our findings provide novel insights into the genetic underpinnings of ESD and they begin to shed light on the physiological function of MF as a male-fate determiner in D. pulex.

Competitive antagonism of insect GABA receptors by 4-substituted 5-(4-piperidyl)-3-isothiazolols.

γ-Aminobutyric acid (GABA) receptors are important targets of parasiticides/insecticides. Several 4-substituted analogs of the partial GABAA receptor agonist 5-(4-piperidyl)-3-isothiazolol (Thio-4-PIOL) were synthesized and examined for their antagonism of insect GABA receptors expressed in Drosophila S2 cells or Xenopus oocytes. Thio-4-PIOL showed weak antagonism of three insect GABA receptors. The antagonistic activity of Thio-4-PIOL was enhanced by introducing bicyclic aromatic substituents into the 4-position of the isothiazole ring. The 2-naphthyl and the 3-biphenylyl analogs displayed antagonist potencies with half maximal inhibitory concentrations in the low micromolar range. The 2-naphthyl analog induced a parallel rightward shift of the GABA concentration-response curve, suggesting competitive antagonism by these analogs. Both compounds exhibited weak insecticidal activities against houseflies. Thus, the orthosteric site of insect GABA receptors might be a potential target site of insecticides.

Clinical characteristics of severe community-acquired pneumonia among younger patients: an analysis of 18 years at a community hospital.

Unlike elderly patients with community-acquired pneumonia whose outcomes are markedly affected by their background characteristics, it appears that the severity of the infection itself contributes to outcomes in younger patients with community-acquired pneumonia. In order to identify clinical characteristics of severe community-acquired pneumonia in younger patients under 60 years old, among such cases prospectively collected at our hospital over a period of 18 years, those meeting the criteria for severe community-acquired pneumonia, as defined in the Infectious Diseases Society of America/American Thoracic Society Guidelines for community-acquired pneumonia, were retrospectively examined and compared to elderly patients with severe community-acquired pneumonia. Younger patients with severe pneumonia accounted for 12.9% of younger hospitalized patients. Although the incidence of severe pneumonia in younger patients was lower than that in elderly patients, its severity may be underestimated by severity assessment based on the conventional guidelines. Thus, attention is required. While Streptococcus pneumoniae and Legionella species were important causative pathogens, atypical pathogens and viruses were also frequently detected. There were only 11 deaths over a period of 18 years. Based on multivariate analysis, the risk factors for aggravation of community-acquired pneumonia among younger patients were age 50 years or older, diabetes mellitus, chronic liver disease, and Legionella pneumonia. Although the mortality rate from community-acquired pneumonia is extremely low in previously healthy younger patients, outcomes might be poor for patients with underlying diseases and those with rapid progression. Multimodal treatments including respiratory management may be appropriate.

Determination by LC-MS of juvenile hormone titers in hemolymph of the silkworm, Bombyx mori.

Juvenile hormone (JH) I, II and III in the hemolymph of the silkworm, Bombyx mori were quantified by liquid chromatography-mass spectrometry (LC-MS). JHs were treated with methanol and trifluoroacetic acid to convert into JH methoxyhydrines (JH-MHs). The key to the analytical condition for JH-MHs was the addition of 5 µM sodium acetate to the eluting solution. Each JH-MH was observed as the sodium adduct ion with good sensitivity. This improved method enabled the titration of JH I, II and III in hemolymph of the silkworm to be monitored from the 3rd instar through to the early pupal stage. A peak of JH I was observed immediately after ecdysis in the 3rd and 4th instar stages. The JH I titer sharply decreased on day 1 and reached the lowest level before ecdysis, but there was no peak at the beginning of the 5th stadium, and no apparent increase was observed until pupation.